Make STUN server mandatory if DERP embedded is enabled

cmd/headscale/cli/utils.go

@@ -124,8 +124,11 @@ func GetDERPConfig() headscale.DERPConfig {
 	serverRegionID := viper.GetInt("derp.server.region_id")
 	serverRegionCode := viper.GetString("derp.server.region_code")
 	serverRegionName := viper.GetString("derp.server.region_name")
-	stunEnabled := viper.GetBool("derp.server.stun.enabled")
-	stunAddr := viper.GetString("derp.server.stun.listen_addr")
+	stunAddr := viper.GetString("derp.server.stun_listen_addr")
+
+	if serverEnabled && stunAddr == "" {
+		log.Fatal().Msg("derp.server.stun_listen_addr must be set if derp.server.enabled is true")
+	}
 
 	urlStrs := viper.GetStringSlice("derp.urls")
 
@@ -152,7 +155,6 @@ func GetDERPConfig() headscale.DERPConfig {
 		ServerRegionID:   serverRegionID,
 		ServerRegionCode: serverRegionCode,
 		ServerRegionName: serverRegionName,
-		STUNEnabled:      stunEnabled,
 		STUNAddr:         stunAddr,
 		URLs:             urls,
 		Paths:            paths,

config-example.yaml

@@ -69,14 +69,12 @@ derp:
     region_code: "headscale"
     region_name: "Headscale Embedded DERP"
 
-    # Enabled by default when embedded DERP is enabled. Listens in UDP at the configured address for STUN connections
-    # to help on NAT traversal.
-    # If DERP is enabled, but STUN is disabled you still need to input an external STUN server in the listen_addr field.
+
+    # Listens in UDP at the configured address for STUN connections to help on NAT traversal.
+    # When the embedded DERP server is enabled stun_listen_addr MUST be defined.
     #
     # For more details on how this works, check this great article: https://tailscale.com/blog/how-tailscale-works/
-    stun:
-      enabled: true
-      listen_addr: "0.0.0.0:3478"
+    stun_listen_addr: "0.0.0.0:3478"
 
   # List of externally available DERP maps encoded in JSON
   urls:

integration_test/etc_embedded_derp/config.yaml

@@ -24,6 +24,5 @@ derp:
     region_id: 999
     region_code: "headscale"
     region_name: "Headscale Embedded DERP"
-    stun:
-      enabled: true
-      listen_addr: "0.0.0.0:3478"
+
+    stun_listen_addr: "0.0.0.0:3478"